exchange 2007 error

Merhabalar

exchange 2007 sisteminde günlüklerde devamlı aşşağıdaki hata mesajı var. araştırdım ama bulamadım

Service MSExchangeMailboxAssistants. An error has been detected due to this exception: Microsoft.Exchange.Assistants.AIGrayException ---> Microsoft.Exchange.Common.GrayException ---> System.ArgumentNullException: Value cannot be null. Parameter name: serverDn at Microsoft.Exchange.Data.Storage.ConnectionCacheKey..ctor(String serverDn, ConnectFlag connectFlags) at Microsoft.Exchange.Data.Storage.ConnectionCachePool.GetConnectionCache(String server, ConnectFlag connectFlags) at Microsoft.Exchange.Data.Storage.ConnectionCachePool.OpenMailbox(String serverDn, String userDn, String mailboxDn, Guid mailboxGuid, Guid mdbGuid, Object identity, ConnectFlag connectFlag, OpenStoreFlag openStoreFlag, CultureInfo cultureInfo, String clientInfoString, Boolean secondTry) at Microsoft.Exchange.Data.Storage.ConnectionCachePool.OpenMailbox(String serverDn, String userDn, String mailboxDn, Guid mailboxGuid, Guid mdbGuid, Object identity, ConnectFlag connectFlag, OpenStoreFlag openStoreFlag, CultureInfo cultureInfo, String clientInfoString) at Microsoft.Exchange.Data.Storage.MailboxSession.Initialize(LogonType logonType, ExchangePrincipal owner, DelegateLogonUser delegateUser, Object identity, OpenMailboxSessionFlags flags) at Microsoft.Exchange.Data.Storage.MailboxSession.CreateMailboxSession(LogonType logonType, ExchangePrincipal owner, DelegateLogonUser delegateUser, Object identity, OpenMailboxSessionFlags flags, CultureInfo cultureInfo, String clientInfoString) at Microsoft.Exchange.Data.Storage.MailboxSession.OpenAsAdmin(ExchangePrincipal mailboxOwner, CultureInfo cultureInfo, String clientInfoString, Boolean useLocalRpc, Boolean ignoreHomeMdb) at Microsoft.Exchange.Data.Storage.MailboxSession.OpenAsAdmin(ExchangePrincipal mailboxOwner, CultureInfo cultureInfo, String clientInfoString, Boolean useLocalRpc) at Microsoft.Exchange.Assistants.DatabaseInfo.GetMailbox(ExchangePrincipal principal, String clientInfo) at Microsoft.Exchange.InfoWorker.Assistants.OOF.OofScheduleStore.ScanForScheduledOof() at Microsoft.Exchange.InfoWorker.Assistants.OOF.OofScheduleStore.Load(Boolean useCache) at Microsoft.Exchange.InfoWorker.Assistants.OOF.OofScheduler..ctor(DatabaseInfo databaseInfo, Boolean useCache) at Microsoft.Exchange.InfoWorker.Assistants.OOF.OofAssistant.OnStartInternal(EventBasedStartInfo startInfo) at Microsoft.Exchange.InfoWorker.Assistants.EventBasedAssistant.OnStart(EventBasedStartInfo startInfo) at Microsoft.Exchange.Assistants.EventBasedAssistantCollection.StartAssistants(EventBasedStartInfo startInfo) at Microsoft.Exchange.Assistants.EventController.Start() at Microsoft.Exchange.Assistants.OnlineDatabase.Start() at Microsoft.Exchange.Assistants.Util.<>c__DisplayClass2.b__0() at Microsoft.Exchange.Common.IL.ILUtil.DoTryFilterCatch(TryDelegate tryDelegate, FilterDelegate filterDelegate, CatchDelegate catchDelegate) --- End of inner exception stack trace --- at Microsoft.Exchange.Common.GrayException.ExceptionCatcher(Object exception) at Microsoft.Exchange.Common.IL.ILUtil.DoTryFilterCatch(TryDelegate tryDelegate, FilterDelegate filterDelegate, CatchDelegate catchDelegate) at Microsoft.Exchange.Common.GrayException.MapAndReportGrayExceptions(UserCodeDelegate tryCode) at Microsoft.Exchange.Assistants.Util.CatchMeIfYouCan(CatchMe function) --- End of inner exception stack trace --- at Microsoft.Exchange.Assistants.Util.CatchMeIfYouCan(CatchMe function) at Microsoft.Exchange.Assistants.Base.CatchMeIfYouCan(CatchMe function). For more information, see Help and Support Center at